Upgrading Drupal

Executed command:

php drush.phar up --security-only

File system before (looked at another machine):

I'm trying to upgrade a big, old, messy site from 7 to 8. I'm using XAMPP to create a local host.

The Drupal 7 site is running fine on the local host. I've installed a clean copy of Drupal 8, and am running the upgrade using the Migrate UI. 

After filling in details of the old site at the credentials section and clicking 'Review Upgrade', I'm sent to [sitename]/upgrade/idconflict and encounter this message: The website encountered an unexpected error. Please try again later.

Can anyone help me?

I've searched this forum and on google on my Drupal 7 to Drupal 8 upgrade problem, but found no success.

I am attempting to upgrade my Drupal 7 site at http://club.my-kart.org to my new install of Drupal 8 at https://my-kart.org/d8

I've done the preparation according to https://www.drupal.org/docs/8/upgrade/preparing-a-site-for-upgrade-to-dr...

Hi everyone -

My 2-person team responsible for a complex subscription site which we are upgrading from Drupal 6 to 7. There are several dozen contrib and custom modules, and many of the contribs have been modified over 8 years. A daunting task, to be sure.

The conversion of our "public" side (converted from Ubercart to Commerce) is nearly complete, and we are about to test the Commerce data that has been migrated from Ubercart by a third party.

Hi,

I'm updating modules by manually deleting module folder and uploading the new version, then I run update.php.

I have always done this way with no problem, but today, trying to update google_analytics module to 2.4 does not work.

I have replaced the files, and connection to my GNU/Linux server, files are replaced. If I run update.php everyhting goes ok, but report page still says it's version 2.3 !!!

I have emptied cache and done everyhting I could, but nothing works.

What can be the problem?

I'm under last 8.6.9 version

Regards

I am using 8.5.10 based on drupal-composer/drupal-project because some of the contribution modules do not correspond to 8.6.
I will update it to 8.6.9 soon.
Generally, in large spaced versions, is it okay to run composer update at once?
Is it better to update to 8.6.9 after updating to 8.6?